Whirlpool bathtubs typically are provided with a plurality of jet inlets, each externally connected to a water and air manifold. In the typical installation, water initially filling the whirlpool bathtub is continually recirculated to the water manifold, by means of a pump, and thence back into the tub, through the jets. Each particular whirlpool bathtub, for greater efficiency of operation, has a particular optimal flow rate (gpm) of recirculating water. The water in the tub is recirculated back to the jets through a suction fitting placed near the bottom of the tub. The suction fitting cover is attached to an interconnect member which is, in turn, affixed to the piping carrying the recirculating water back to the water manifold and thence to the jets. Suction fittings of the prior art are typically metallic covers having a plurality of small-sized holes, slots, and the like provided therein, mounted onto the recirculating pipe inlet. Such suction fittings have typically been mounted by means of a central support affixed to the interconnect member.
The problem with such suction fittings has been that long hair of a person using the bathtub may become entrapped within the holes of the suction fitting and/or the central support, mounting it to the pipe inlet. The problem is compounded if a high suction is developed at the flow rate required or employed by the given whirlpool bath system.
Suction fittings for whirlpool bathtubs are rated in terms of the amount of suction, in pounds, generated at a particular flow rate, in gallons per minute (gpm), flowing through the suction fitting. The amount of suction generated at a particular flow rate has become very important, from a safety point of view. Thus, under recently-enacted standards of the International Association of Plumbing and Mechanical Officials (IAPMO Standard SPS 1-83), no more than a five pound pull is permitted at the flow rate required by the particular whirlpool bath plumbing installation.
In view of the foregoing, the need for new types of suction fittings, which have a reduced pull for a given flow rate of recirculating water, is apparent.